Ricoh BR-C1a Basic Service Training page 316

 Four paper height sensors [A] attached to the front of the right
tray monitor the amount of paper in the tray.
 As the actuator on the right support rod rises, it de-activates each
sensor in turn to trigger 5 levels of remaining paper alerts on the
operation panel.
 When the tray is full, no sensors are de-activated (100%).
 The paper end sensor [B] indicates when the tray is out of paper
after the last sheet feeds from the tray.
Slide 316
No additional notes
Tray 1 (Tandem Tray)
Remaining Paper Detection
316
BR-C1 Training